1. Field of Invention
The invention is related to an LED illuminator, and more particularly to an LED illuminator with ability of stable brightness applied in emergent lighting and night lighting.
2. Related Art
In the old times, people worked in the day and rested in the night. The situation indicated that the light is very important to people livings. People relied on the sunlight such that all activities were restricted when the night came. This situation did not get better until the appearance of the illuminating devices. Under the continuous development of the illuminating devices, there are various kinds of illuminators form portable flashlight to search light. Gradually, the illuminating devices are transferred from light bulbs to LEDs.
The LEDs have been widely employed because of the small volume, long usage life, lower power consumption, and less easy damaged than light bulbs. The improving brightness of the LED is also one of the key factors. The conventional LED illuminators employ light emitting diode (LED) as the illuminating element because of better brightness and lower power consumption. However, when the working voltage is below a predetermined level, usually about 3 volts, the brightness is affected and becomes unstable. The unstable light may damage people's eyes.
It is concluded that remaining the brightness of the LED illuminators effectively is necessary.